"It's pleasing to see that our U20s players continue to work hard and force their way into selection," explained Director of Rugby Eddie Jones.

"We've seen Andy Saull take his opportunities well this season and Sunday is a chance for others within the squad to do the same. We've had two good wins in the European Challenge Cup and we need to build on that momentum over the next few weeks."

Northampton Saints return to Vicarage Road sees director of rugby Jim Mallinder calling on his players to sharpen their act.

The Saints' last trip to Watford was in the Guinness Premiership at the end of September, a match they lost to the Saracens. Although they have won their EDF Energy Cup and European games in recent weeks Mallinder said that the club cannot rest on its laurels.

"We've only won three games!" the Saints' boss said.

"It is nothing to get complacent about. While we scored tries against Montpellier there were plenty of mistakes that spoiled several other chances. If we do the same against Saracens we will not do as well.

"We saw that in the Premiership match there in September where we created some chances, could not finish them off and lost the game.

"I'm looking for the team to eliminate the errors, play to our game plan and put in a good performance. We want to win the game but know that we are going to have to work extremely hard to do so."

Form: Saracens have won five of their last six matches in all competitions - the loss being 17-26 to the Scarlets in the opening round of the EDF Energy Cup. Saracens, who were semi-finalists in the EDF Energy Cup last season, have lost their last three encounters in the competition. Northampton Saints have won their last three matches in all competitions including the 30-17 victory at home to Bristol in round one of the EDF Energy Cup. The Saints have won their last two games in the EDF Energy Cup. Saracens have won six of their last seven encounters with the Saints, whilst Northampton's last win at Vicarage Road was 22-18 in the Premiership on 15 February 2004.